Patents by Inventor Chandrashekhar P. Pathak

Chandrashekhar P. Pathak has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20040072961
    Abstract: Gel-forming macromers including at least four polymeric blocks, at least two of which are hydrophobic and at least one of which is hydrophilic, and including a crosslinkable group are provided. The macromers can be covalently crosslinked to form a gel on a tissue surface in vivo. The gels formed from the macromers have a combination of properties including thermosensitivity and lipophilicity, and are useful in a variety of medical applications including drug delivery and tissue coating.
    Type: Application
    Filed: August 27, 2003
    Publication date: April 15, 2004
    Applicant: Focal, Inc
    Inventors: Chandrashekhar P. Pathak, Shikha P. Barman, C. Michael Philbrook, Amarpreet S. Sawhney, Arthur J. Coury, Luis Z. Avila, Mark T. Kieras
  • Publication number: 20040023842
    Abstract: Biocompatible crosslinked polymers, and methods for their preparation and use, are disclosed in which the biocompatible crosslinked polymers are formed from water soluble precursors having electrophilic and nucleophilic groups capable of reacting and crosslinking in situ. Methods for making the resulting biocompatible crosslinked polymers biodegradable or not are provided, as are methods for controlling the rate of degradation. The crosslinking reactions may be carried out in situ on organs or tissues or outside the body. Applications for such biocompatible crosslinked polymers and their precursors include controlled delivery of drugs, prevention of post-operative adhesions, coating of medical devices such as vascular grafts, wound dressings and surgical sealants.
    Type: Application
    Filed: February 24, 2003
    Publication date: February 5, 2004
    Applicant: Incept
    Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Peter G. Edelman
  • Publication number: 20040002456
    Abstract: Materials, methods, and compositions for making crosslinked albumin hydrogels are included in the application. Embodiments include a biocompatible material of albumin crosslinked with an n-functional crosslinking agent wherein n is at least 3. Other embodiments include a cross-linking agent having a polyalkylene oxide member. Other embodiments include a system for administering an albumin material, the system having albumin and a crosslinking agent that reacts with the albumin to form a crosslinked material made of crosslinked albumin. Another embodiment is a method of making a biocompatible material that includes a step of mixing albumin with an n-functional crosslinking agent wherein n is at least 3.
    Type: Application
    Filed: February 11, 2003
    Publication date: January 1, 2004
    Applicant: Incept LLC
    Inventor: Chandrashekhar P. Pathak
  • Patent number: 6639014
    Abstract: Gel-forming macromers including at least four polymeric blocks, at least two of which are hydrophobic and at least one of which is hydrophilic, and including a crosslinkable group are provided. The macromers can be covalently crosslinked to form a gel on a tissue surface in vivo. The gels formed from the macromers have a combination of properties including thermosensitivity and lipophilicity, and are useful in a variety of medical applications including drug delivery and tissue coating.
    Type: Grant
    Filed: April 2, 2002
    Date of Patent: October 28, 2003
    Assignee: Focal, Inc.
    Inventors: Chandrashekhar P. Pathak, Shikha P. Barman, C. Michael Philbrook, Amarpreet S. Sawhney, Arthur J. Coury, Luis Z. Avila, Mark T. Kieras
  • Patent number: 6632446
    Abstract: Water soluble macromers are modified by addition of free radical polymerizable groups, such as those containing a carbon-carbon double or triple bond, which can be polymerized under mild conditions to encapsulate tissues, cells, or biologically active materials. The polymeric materials are particularly useful as tissue adhesives, coatings for tissue lumens including blood vessels, coatings for cells such as islets of Langerhans, and coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules.
    Type: Grant
    Filed: October 23, 2000
    Date of Patent: October 14, 2003
    Assignee: The Board of Regents, University of Texas System
    Inventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill, Syed F. A. Hossainy
  • Publication number: 20030162841
    Abstract: Biocompatible crosslinked-polymers, and methods for their preparation and use, are disclosed in which the biocompatible crosslinked polymers are formed from water soluble precursors having electrophilic and nucleophilic groups capable of reacting and crosslinking in situ. Methods for making the resulting biocompatible crosslinked polymers biodegradable or not are provided, as are methods for controlling the rate of degradation. The crosslinking reactions may be carried out in situ on organs or tissues or outside the body. Applications for such biocompatible crosslinked polymers and their precursors include controlled delivery of drugs, prevention of post-operative adhesions, coating of medical devices such as vascular grafts, wound dressings and surgical sealants.
    Type: Application
    Filed: February 25, 2003
    Publication date: August 28, 2003
    Applicant: Incept
    Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Peter G. Edelman
  • Patent number: 6602975
    Abstract: Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.
    Type: Grant
    Filed: October 22, 2001
    Date of Patent: August 5, 2003
    Assignee: Board of Regents, The University of Texas System
    Inventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill
  • Patent number: 6596471
    Abstract: Herein is disclosed a method of cross-linking a tissue, comprising treating the tissue under effective cross-linking conditions with a diunsaturated organic compound comprising structure I: wherein R, R′, and R″ are each independently an organic moiety having from 1 to 20 carbon atoms. Also disclosed is a cross-linked biological tissue produced by treating the tissue according to the above method.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: July 22, 2003
    Assignee: Carbomedics Inc.
    Inventors: Chandrashekhar P. Pathak, Mark A. Moore, Richard E. Phillips, Jr.
  • Patent number: 6566406
    Abstract: Biocompatible crosslinked polymers, and methods for their preparation and use, are disclosed in which the biocompatible crosslinked polymers are formed from water soluble precursors having electrophilic and nucleophilic groups capable of reacting and crosslinking in situ. Methods for making the resulting biocompatible crosslinked polymers biodegradable or not are provided, as are methods for controlling the rate of degradation. The crosslinking reactions may be carried out in situ on organs or tissues or outside the body. Applications for such biocompatible crosslinked polymers and their precursors include controlled delivery of drugs, prevention of post-operative adhesions, coating of medical devices such as vascular grafts, wound dressings and surgical sealants.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: May 20, 2003
    Assignee: Incept, LLC
    Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Peter G. Edelman
  • Publication number: 20030087985
    Abstract: This invention provides novel methods for the formation of biocompatible membranes around biological materials using photopolymerization of water soluble molecules. The membranes can be used as a covering to encapsulate biological materials or biomedical devices, as a “glue” to cause more than one biological substance to adhere together, or as carriers for biologically active species.
    Type: Application
    Filed: July 19, 2001
    Publication date: May 8, 2003
    Inventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Syed F.A. Hossainy, Jennifer L. Hill-West
  • Publication number: 20030077272
    Abstract: Proteinaceous gels having visualization agents and methods of use thereof are disclosed herein. Further, polymeric crosslinking agents are disclosed that have an inert water soluble polymeric component, biodegradable components, functional components reactive with chemical groups on a protein, for example, amine or thiol groups. The inert polymeric component may be flanked at each end with a biodegradable component which is flanked at each end with a protein reactive functional component. A polymeric crosslinking agent is disclosed having a biodegradable component, polyalkylene oxide, and at least three reactive functional groups that are each capable of forming a covalent bond in water with at least one functional group such as an amine, thiol, or carboxylic acid.
    Type: Application
    Filed: November 13, 2002
    Publication date: April 24, 2003
    Applicant: Incept LLC
    Inventor: Chandrashekhar P. Pathak
  • Patent number: 6528107
    Abstract: A method is provided for producing antimicrobial, antithrombogenic medical devices. The method employs an antimicrobial treatment process wherein an antimicrobial agent is dissolved in an appropriate solvent and the resulting solution is contacted with a portion of a medical device of interest. The antimicrobial treatment process is advantageously performed without the need for additional compounds to facilitate antimicrobial agent uptake into the device. The method further comprises an antithrombogenic treatment process wherein antithrombogenic agents or materials are applied or otherwise associated with at least some portion of the medical device.
    Type: Grant
    Filed: July 22, 1999
    Date of Patent: March 4, 2003
    Assignee: Sulzer Carbomedics Inc.
    Inventors: Joseph A. Chinn, Richard E. Phillips, Jr., Joseph A. Sauter, R. Michael Casanova, Chandrashekhar P. Pathak, Mark A. Moore, L. Diane Bruce
  • Publication number: 20030021825
    Abstract: Undesired agents, which can reduce biocompatibility, can be selectively and substantially removed from implantable medical devices using methods of the present invention. Pressure and temperature of a supercritical fluid are adjusted to selectively remove one or more undesired agents from an implantable medical device perfused with the supercritical fluid. Treated implantable medical devices comprising at least about 75 wt % less of at least one undesired agent than the same device before undergoing a treatment are also disclosed.
    Type: Application
    Filed: October 1, 2002
    Publication date: January 30, 2003
    Inventors: Chandrashekhar P. Pathak, Joseph A. Chinn, Randall J. Thoma
  • Publication number: 20030012734
    Abstract: Biocompatible crosslinked polymers, and methods for their preparation and use, are disclosed in which the biocompatible crosslinked polymers are formed from water soluble precursors having electrophilic and nucleophilic functional groups capable of reacting and crosslinking in situ. Methods for making the resulting biocompatible crosslinked polymers biodegradable or not are provided, as are methods for controlling the rate of degradation. The crosslinking reactions may be carried out in situ on organs or tissues or outside the body. Applications for such biocompatible crosslinked polymers and their precursors include controlled delivery of drugs, prevention of post-operative adhesions, coating of medical devices such as vascular grafts, wound dressings and surgical sealants. Visualization agents may be included with the crosslinked polymers.
    Type: Application
    Filed: November 9, 2001
    Publication date: January 16, 2003
    Applicant: Incept LLC.
    Inventors: Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Peter G. Edelman
  • Publication number: 20020151650
    Abstract: Gel-forming macromers including at least four polymeric blocks, at least two of which are hydrophobic and at least one of which is hydrophilic, and including a crosslinkable group are provided. The macromers can be covalently crosslinked to form a gel on a tissue surface in vivo. The gels formed from the macromers have a combination of properties including thermosensitivity and lipophilicity, and are useful in a variety of medical applications including drug delivery and tissue coating.
    Type: Application
    Filed: April 2, 2002
    Publication date: October 17, 2002
    Applicant: Focal, Inc.
    Inventors: Chandrashekhar P. Pathak, Shikha P. Barman, C. Michael Philbrook, Amarpreet S. Sawhney, Arthur J. Coury, Luis Z. Avila, Mark T. Kieras
  • Patent number: 6465001
    Abstract: Water soluble macromers are modified by addition of free radical polymerizable groups, such as those containing a carbon-carbon double or triple bond, which can be polymerized under mild conditions to encapsulate tissues, cells, or biologically active materials. The polymeric materials are particularly useful as tissue adhesives, coatings for tissue lumens including blood vessels, coatings for cells such as islets of Langerhans, and coatings, plugs, supports or substrates for contact with biological materials such as the body, and as drug delivery devices for biologically active molecules. A medical condition at a localized site is treated by applying a polymerization initiator and then applying a substantially water-soluble, degradable macromer of at least 200 mw and having at least two crosslinkable substituents, and polymerizing the macromer to form a crosslinked polymeric material at the site.
    Type: Grant
    Filed: March 3, 1998
    Date of Patent: October 15, 2002
    Assignee: Board of Regents, The University of Texas Systems
    Inventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet Sawhney, Neil Desai, Syed Hossainy, Jennifer L. Hill-West
  • Publication number: 20020119563
    Abstract: Herein is disclosed a method of cross-linking a tissue, comprising treating the tissue under effective cross-linking conditions with a diunsaturated organic compound comprising structure I: 1
    Type: Application
    Filed: December 21, 2000
    Publication date: August 29, 2002
    Inventors: Chandrashekhar P. Pathak, Mark A. Moore, Richard E. Phillips
  • Publication number: 20020114775
    Abstract: Methods and compositions are provided for preparing protein concentrates from protein comprising aqueous compositions. In the subject methods, an initial protein comprising aqueous compositions, such as whole blood or a derivative thereof, is contacted with a non-protein denaturant hydrogel under conditions sufficient for a substantial amount of water present in the composition to be absorbed by the hydrogel, resulting in the production of a protein concentrate, such as a fibrinogen rich composition. Of particularl interest is the use of the subject methods to prepare fibrinogen rich compositions, where such compositions produced according to the subject invention are useful in fibrin sealants, drug delivery vehicles and in a number of other diverse applications.
    Type: Application
    Filed: February 5, 2002
    Publication date: August 22, 2002
    Applicant: Incept LLC
    Inventor: Chandrashekhar P. Pathak
  • Publication number: 20020111532
    Abstract: A method of cross-linking a tissue, comprising treating the tissue under effective cross-linking conditions with a fluid comprising a compound comprising P(CH2OH)3Xn, wherein X is selected from C1-C10 carboxyl, sulfonic acid, sulfonic acid salts, C1-C10 alcohol, or halogens, and n is an integer from 0 to 2, inclusive, and all —X and —CH2OH groups are bonded to the phosphorus atom. In one embodiment, the compound is &bgr;-(tris(hydroxymethyl)phosphino)proprionic acid (THPP).
    Type: Application
    Filed: December 19, 2000
    Publication date: August 15, 2002
    Inventors: Chandrashekhar P. Pathak, Mark A. Moore, Richard E. Phillips, Alan Adams
  • Publication number: 20020091229
    Abstract: Hydrogels of polymerized and crosslinked macromers comprising hydrophilic oligomers having biodegradable monomeric or oligomeric extensions, which biodegradable extensions are terminated on free ends with end cap monomers or oligomers capable of polymerization and cross linking are described. The hydrophilic core itself may be degradable, thus combining the core and extension functions. Macromers are polymerized using free radical initiators under the influence of long wavelength ultraviolet light, visible light excitation or thermal energy. Biodegradation occurs at the linkages within the extension oligomers and results in fragments which are non-toxic and easily removed from the body. Preferred applications for the hydrogels include prevention of adhesion formation after surgical procedures, controlled release of drugs and other bioactive species, temporary protection or separation of tissue surfaces, adhering of sealing tissues together, and preventing the attachment of cells to tissue surfaces.
    Type: Application
    Filed: October 22, 2001
    Publication date: July 11, 2002
    Applicant: Board of Regents, The University of Texas System Texas
    Inventors: Jeffrey A. Hubbell, Chandrashekhar P. Pathak, Amarpreet S. Sawhney, Neil P. Desai, Jennifer L. Hill